John Ernest, Duke of Saxe-Coburg

John Ernest
Duke of Saxe-Coburg Landgrave of Thuringia
File:1521 Johann Ernst.JPG
Reign	1542–1553
Predecessor	John Frederick I
Successor	John Frederick II
Born	(1521-05-10)10 May 1521 Coburg
Died	Coburg
House	House of Wettin Ernestine Line
Father	John, Elector of Saxony
Mother	Margaret of Anhalt-Köthen
Religion	Lutheranism

John Ernest (German: Johann Ernst) (10 May 1521 – 8 February 1553) was a Duke of Saxe-Coburg.

John Ernest was born in Coburg as the third (but second surviving and the youngest) son of John, Elector of Saxony, and his second wife Margaret of Anhalt-Köthen. After the death of his father (1532), his half-brother, John Frederick I, assumed the title of Elector of Saxony; John Ernest took part with him in the rule over the Electorate of Saxony.

In 1542 John Frederick I decided to rule alone, and ceded to John Ernest the Franconian areas of the Wettin family lands (Coburg, Eisfeld, etc.); but it was not until 1547 (after the Battle of Mühlberg) when John Ernest could govern undisturbed in Coburg. After he died unmarried and childless in Coburg, the city fell for a few months to John Frederick — dismissed from the imperial detention — before his death, and then, to his three sons, which governed the Ernestine lands together from 1554 for some years.